Ours uses a combination of rote learning, 'games' (like fizz buzz etc), strategies (doubling/halving known facts etc), home learning and reward systems (certificates for completed levels and frequent testing). We don't really have a whole school policy (except the reward system) but this is what most people do. Being able to apply times table facts is essential - e.g. using what you know to solve a question like twenty people need four pens each...etc. They also need to know the inverse - i.e. division facts. I feel we tail off times tables a bit in upper KS2, when the lower set children are often weak in this, and mental maths generally (a problem the school is now trying to address).